Grieving a center manager who works a lower seniority employee

I'm a cover driver who was sent back to twilight on monday, march 3rd. On that day, I called in and used a sick day. The new twilight manager, who was formerly my on road supervisor until about a month ago, called me and tried to convince me to come in. I told him I was sick, and that I'd see him tomorrow. He then stated that he was going to get with my center manager and "go over my file" because I had been calling in sick way too much. I told him I would see him tomorrow night and we would talk.

The following night on tuesday, march 4th, I reported to work and was told that an employee had just quit and I was covering his trailer the rest of the week. I worked this trailer most of tuesday night and only once did the twilight manager come visit me. Nothing about calling in sick, just said hey how're you doing etc then left.

On wednesday, march 5th at about 10:30 one of my on road supervisors called me and told me I was being called back, and to report to work tomorrow for driving. I called him back and verified that I'd be driving tomorrow. Later in the day, a cover driver I work with that is right below me in seniority called me. He said that they had called him tuesday night and told him to report to work wednesday for driving. That night I called in to use another sick day. This time, the twilight manager told me he had already "gotten with my center manager" and that I was looking at a warning letter, and a 1 day suspension due to excessive sick calls. I told him "if you need to talk to my center manager and decide on what type of disciplinary action you need to take, I'll discuss it with him tomorrow when I report to work."

This morning I went to work and did not hear a single word about a warning letter or a suspension.

Is there any action I can take regarding the working of an employee with less seniority than myself? I feel like the twilight manager and my center manager got together and decided they were going to punish me for calling in sick. Which puzzles me because my center manager is usually very straight up, doesn't play games or do things like this.

that being said why would u want to, it seems that u are calling in sick whenever you want to and are doing it entirely too much, if u take action against them then they seem to have more then enough to do the same agaisnt you